Sheet metal working machines



Nov. 17, 1964 E. HANNI SHEET METAL WORKING MACHINES 2, Sheets-Sheet 1Filed June 24, 1960 2 Sheets-Sheet 2 Filed June 24, 1960 United StatesPatent 7453 11 Claims. c1. 82-54) The present invention concerns sheetmetal working machines for the trimming of cylindrical and non-circularsheet metal parts and having two tool shafts of which one is mounted ina movable bearing member and the other in the machine frame.

The object of the invention is to provide a sheet metal working machinewith which the cutting or trimming of cylindrical and non-cylindricalsheet metal parts is possible by the copy-method as well as by thefollow-on method.

In the copy-method a tool is arranged in the frame mounted shaft, whichtool has the inner shape of the workpiece to be machined whilst themovable bearing body, for example a rocker arm, carries a circularknife. According to the follow-on method two driven circular knives areused. The rocker arm, which carries one of the knives, must be pressedwith as great a force as possible against the other cutting knife andthus the workpiece passes between the circular knives.

According to the invention a sheet metal working machine has a toolshaft with cutting knives arranged in the machine frame and a movabletool shaft with corresponding cutting knives pivotally mounted in arocker arm opposite this tool shaft and is characterised in that thereis pivotally mounted on the machine frame an operating catch under theinfluence of a control arrangement, which operating catch co-operates inone pivot position with the movable bearing member and locks thistemporarily in the fully open position for removal of a finished cutworkpiece from the machine and insertion of a new workpiece between thecutting knives and in another pivot position forms a part of atransmission for increasing the cutting pressure. The locking of therocker arm is suitably effected after a complete rotation of the framemounted tool shaft at the moment when the distance between the twoshafts has reached a maximum.

The invention will now be described further, by way of example only,with reference to the accompanying drawings illustrating one embodimentthereof, in which:

FIG. 1 shows, in plan view, a diagrammatic representation of the sheetmetal working machine for use in accordance with the follow-on method;

FIG. 2 shows a detail of FIG. 1 in another working position;

FIG. 3 shows the sheet metal working machine for use in accordance withthe copy-method in a first working position;

FIG. 4 is the same detail as FIG. 3 in the locked position;

FIG. 5 shows the construction of the movable shaft with cutting knives;

FIG. 6 shows, in a partial sectional view the tools for cutting of acylindrical sheet metal part; and

FIG. 7 shows in a similar view the tools for cutting a non-cylindricalpart.

A sheet metal working machine has a frame 1 which carries a horizontalwork table 2. In the frame there is provided a driving motor, forexample, an electric motor 3 which via an infinitely variable device 4drives the shaft 5 of an electro-magnetic clutch 6. The clutch 6 is inengagement with a chain drive 7 which drives the shaft 8 of a Worm 9.The worm wheel 19 with which the worm 9 co-operates Serves to drive thetool shaft 11, said shaft 11 being firmly mounted in the frame 1 andcarrying a cutting tool 12.

In addition a movable bearing member in the form of a rocker arm 13 isprovided which is pivotably mounted in the frame about a vertical shaft14. On the rocker 13 is mounted a tool shaft 14', said shaft 14'carrying a cutting tool 15 and being movable with the arm. The toolshaft 14' is driven by the tool shaft 11 through a chain drive 16provided between the tool shaft 11 and the tool shaft 14'. The shank 15'(see FIG. 5) of the tool 15 is mounted on the end of the tool shaft 14'.If the tool 15 is to be freely rotatable then a ball bearing assembly isused for the mounting of the shank. If a fixed connection is requiredthen, as can be seen in FIG. 5, spring plates 17 are used, the latterbeing tensioned by a nut 18 to provide the fixed connection.

The extremity of the rocker arm 13 carries a spring loaded lever 19,said lever being rotatably mounted on a bolt 20 and held in the positionshown in FIG. 2 under the influence of a spring 37. The part of thelever 19 directed towards the shaft 14' is connected, by a bolt 21, tothe piston rod 22 of a piston (not shown), arranged in an air cylinder23. In the working position as illustrated in FIG. 1 (follow-on method)the nose of the lever 19 extends beyond the arm 13, and co-operates withthe hook 25 of an operating catch 26 in that the nose 24- engages thehook 25. The catch 26 is pivotally mounted in the frame 1 and has holes27 whereby adjustment of the position thereof might be effected. Theremote end of the catch 26 is provided with an arm 28 pivotally coupledto the piston rod 29 of a piston 32 located in an air cylinder 30. Theair cylinder 30 is pivotably mounted in the frame by means of a lug 31.The piston 32 moves against the action of a compression spring 33, thelatter tending to hold the piston in the position illustrated in FIG. 1.

In the position shown in FIGS. 1 and 2 the sheet metal Working machineis arranged for the cutting or trimming of large cylindrical andnon-cylindrical cup shaped or similar sheet metal parts With variablespeed ratios of the main shafts in accordance with the follow-on method.The workpiece to be machined is cut by means of the two cutting tools 12and 15, both cutting tools being driven. After the workpiece has beenbrought into the machining position while the arm 13 is pivoted to anopen position, the arm 13 is pivoted in clockwise direction so that thecutting tool 15 contacts the workpiece. For the pivoting of the armrelatively little force is needed and such force as is necessary isapplied by the air cylinder 23. After the working position has beenreached the operating catch 26 is pivoted, under the action of thecompression spring 33, in anti-clockwise direction as there is no air inthe cylinder 30. The nose 24 is held by the hook 25 as can be seen inFIG. 1. In this way there results a lever transmission with the arms aand b which transmission efiects the increase of the force exercised bythe air cylinder 23 in the direction of the arrow I in the ratio a/b.The arm 13 is therefore brought, with relatively small expenditure offorce, into the working position. However, as soon as the cutting tool15 contacts the sheet metal of the workpiece the force is multiplied andis then sufiicient for the cutting of the material. After the Workingprocedure is terminated air is applied to the cylinder 34 so that thespring 33 is compressed and the operating catch 26 again pivoted intothe initial position.

If the sheet metal working machine described is used in accordance withthe copy-method the tool on the shaft 11 is replaced by a tool 36 havingthe shape of the workpiece 34 as shown in FIGS. 3 and 4 and the pivotingmovement of the lever 19 is prevented. For this purpose a locking pin 35is used, said pin .35 firmly connecting the lever 19 to the arm 13. Inthe initial position the arm 13 is in just less than the fully openposition, and is supported on the pawl 26 (FIG. 4). In this manner thecatch is firmly held although, against the action of the compressionspring 33, the pressure in the cylinder 39 tends to effect a pivoting ofthe catch in clockwise direction. As soon as the cutting tool 12, andthus the workpiece 34, begins to rotate in a clockwise direction the arm13 is raised a little by the edge 34 of the workpiece 34, whereupon thecatch 26, under the action of the air cylinder 30, is pivoted in aclockwise direction and the locking of the arm is released (FIG. 3). Thearm 13 can accurately follow the contours of the rotating workpiece 34-as the arm 13 is pressed resiliently against the workpiece 34 by the aircylinder 23. Shortly before completion of the first rotation of theworkpiece the air in cylinder 39 is released by a control device Cschematically indicated in FIG. 1 so that the compression spring 33acting in the direction of the arrow P1 pivots the catch 26 into thelocking position seen in FIG. 4 shortly before the rocker arm 13 hasbeen brought by the edge 34- into its fully open position. On furtherrotation of the workpiece the arrn remains in the locked open positionso that the finished cut workpiece can be taken off from the tool. Afterthe next workpiece is put in place, the air pressure is again applied tocylinder 30, to compress spring 33 in preparation for the next cycle.

The sheet metal working machine can be used in a simple manner both forthe cutting of workpieces in accordance with the follow-on method andthe copymethod whereby the conversion is effected in an extremely simplemanner.

What I claim is:

1. Sheet metal working machine for trimming cylindrical andnon-cylindrical sheet metal parts, said machine comprising a machineframe, a movable bearing member mounted on said frame, two tool shaftsof which one is mounted in said movable bearing member and the other onsaid machine frame, an operating catch pivotally mounted on said machineframe movable under the influence of a control device, said operatingcatch cooperating in one pivot position with the movable hearing memberfor temporarily locking the same in a fully open position and in anotherpivot position forms a part of a transmission for increasing the cuttingpressure, said movable bearing member being formed as a swing armpivotally mounted about an axis, a lever carried by said swing arm atthe end remote from its pivoted axis, said lever being pivotedintermediate the ends thereof, said lever having a nose-like endextending beyond the swing-arm and being adapted to co-o-perate with theoperating catch in that position of the swing arm in which the latter ispivoted toward the frame mounted tool shaft, and operating meansconnected to the other end of said lever for moving the same in adirection so as to move said tool shaft in said movable bearing membertoward the other tool shaft and in oppoiste direction for separatingsaid shafts to a maximum.

2. Sheet metal working machine as ciaimed in claim 1, in which saidoperating means includes an air cylinder, piston and piston rod, whichlatter is connected to said other end of said lever.

3. Sheet metal working machine as claimed in claim 1, in which saidlever is lockable in one pivot position by a locking pin.

4. A machine for trimming cylindrical and non-cylindrical sheet metalparts comprising, in combination, a machine frame; a first tool shaftturnably carried by said frame; a first rotary tool carried by saidfirst shaft; a swing arm pivotally mounted at one end thereof in saidframe; a second tool shaft turnably mounted on said swing arm extendingsubstantially parallel to said first tool shaft; :1 second rotary toolmounted on said second tool shaft, said swing arm being pivotablebetween an open position in which said tools are spaced from each otherpermitting placing of a sheet metal part to be trimmed between saidtools and a working position in which said tools are closely adjacenteach other so that a sheet metal part placed between the tools will beengaged on opposite surface portions by said tools; drive meansoperatively connected to said shafts for turning the same about theiraxes; a lever mounted intermediate its ends on the other end of said armfor tilting movement about a pivot axis parallel to the axes of saidshafts, said lever having at one end a noselike extension projectingbeyond said ot er end of said arm; an operating catch tiltably mountedon said machine frame movable between a first position tilted away fromsaid one end of said lever permitting movement of said arm to said openposition and a second position engaging said noselike extension of saidlever; means connected to said operating catch for moving the samebetween the positions thereof; and operating means connected to theother end of said lever for moving said lever and thereby said armcarrying said lever between said open position and said workingposition.

5. A machine as set forth in claim 4 wherein said operating catch isformed with a hook and wherein said noselike extension of said leverengages under said hook of said catch during trimming of the cylindricalsheet metal parts.

6. A machine as set forth in claim 5 in which the distance of the pivotaxis of said lever from said one end of said lever is smaller than thedistance from the other end thereof so that when said noselike extensionof said lever is engaged under said hook and said operating means movessaid lever so as to move said arm from its open towards its workingposition, said lever and said arm provide for a lever arrangementincreasing the pressure at which said tools are pressed against oppositesurface portions of a sheet metal part placed between the tools.

7. A machine as set forth in claim 4 and including locking means mountedon said arm and cooperating with said lever for locking the same infixed position to said swing arm when said machine is used for trimmingof non-cylindrical sheet metal parts.

8. A machine as set forth in claim 7 in which said one end of saidlever, while said lever is locked by said locking means, engages saidoperating catch in said second position for momentarily locking said armin said open position.

9. A machine as set forth in claim 7 wherein said means for moving saidcatch includes spring means for moving said catch to said first positionwhen said one end of said lever is lifted from said catch duringrotation og said non-cylindrical tool.

10. A machine for trimming cylindrical and noncylindrical sheet metalparts comprising, in combination, a machine frame; a movable bearingmember mounted on said frame; two tool shafts, one of said shafts beingmounted in said movable bearing member and the other on said machineframe; an operating catch pivotally mounted on said frame movable underthe influence of a control device, said operating catch cooperating inone pivot position with the movable bearing member for temporarilylocking the same in a fully open position and in another pivot positionforms part of a transmission for increasing the cutting pressure, saidmovable bearing member being formed as a swing arm mounted on said framepivotally about an axis; a lever carried by said swing arm at the endremote from its pivot axis, said lever being pivoted intermediate theends thereof and having a noselike end extending beyond the swing armand being adapted to cooperate with the operating catch in that positionof the swing arm in which the latter is pivoted toward the frame-mountedtool shaft; and a locking means carried by said swing arm andcooperating with said lever for locking the same in fixed positionReferences Cited in the file of this patent to Said UNITED STATESPATENTS 11. A machine set forth 1n claim 10 and lncludmg 310 804 I d J20 1885 operating means connected to said lever for piVOt ng Said g u 51910 swing arm carrying said lever to separate said tool shafts 5 173223 B O 0 1929 by a maximum, said operating means including an air 2 56 3 1930 I v cylinder, piston and plStOn rod, the latter bemg connected2,420,142 Levin May 6, 1947 to said lever.

1. SHEET METAL WORKING MACHINE FOR TRIMMING CYLINDRICAL AND NON-CYLINDRICAL SHEET METAL PARTS, SAID MACHINE COMPRISING A MACHINE FRAME, A MOVABLE BEARING MEMBER MOUNTED ON SAID FRAME, TWO TOOL SHAFTS OF WHICH ONE IS MOUNTED IN SAID MOVABLE BEARING MEMBER AND THE OTHER ON SAID MACHINE FRAME, AN OPERATING CATCH PIVOTALLY MOUNTED ON SAID MACHINE FRAME MOVABLE UNDER THE INFLUENCE OF A CONTROL DEVICE, SAID OPERATING CATCH COOPERATING IN ONE PIVOT POSITION WITH THE MOVABLE BEARING MEMBER FOR TEMPORARILY LOCKING THE SAME IN A FULLY OPEN POSITION AND IN ANOTHER PIVOT POSITION FORMS A PART OF A TRANSMISSION FOR INCREASING THE CUTTING PRESSURE, SAID MOVABLE BEARING MEMBER BEING FORMED AS A SWING ARM PIVOTALLY MOUNTED ABOUT AN AXIS, A LEVER CARRIED BY SAID SWING ARM AT THE END REMOTE FROM ITS PIVOTED AXIS, SAID LEVER BEING PIVOTED INTERMEDIATE THE ENDS THEREOF, SAID LEVER HAVING A NOSE-LIKE END EXTENDING BEYOND THE SWING-ARM AND BEING ADAPTED TO CO-OPERATE WITH THE OPERATING CATCH IN THAT POSITION OF THE SWING ARM IN WHICH THE LATTER IS PIVOTED TOWARD THE FRAME MOUNTED TOOL SHAFT, AND OPERATING MEANS CONNECTED TO THE OTHER END OF SAID LEVER FOR MOVING THE SAME IN A DIRECTION SO AS TO MOVE SAID TOOL SHAFT IN SAID MOVABLE BEARING MEMBER TOWARD THE OTHER TOOL SHAFT AND IN OPPOSITE DIRECTION FOR SEPARATING SAID SHAFTS TO A MAXIMUM. 